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Homework Help: Helplessly Confused

  1. Sep 9, 2004 #1
    Calculate the time it takes a train to make a 48 km trip in the following two situations. Assume that at each station the train accelerates at a rate of 2.0 m/s2 until it reaches 50 km/h, then stays at this speed until its brakes are applied for arrival at the next station, at which time it decelerates at -3.0 m/s2. Assume it stops at each intermediate station for 20 s.

    (a) The stations at which the trains must stop are 0.60 km apart.

    I'm confused...
  2. jcsd
  3. Sep 9, 2004 #2


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    This is a step by step problem. What do you know? do you know constant acceleration equations?
  4. Sep 9, 2004 #3


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    physicsss, if you try and start on the problem, we can guide you further. If you don't tell us what you've tried or what ideas you have, we really can't help you.
  5. Sep 10, 2004 #4
    I'd start with sketches dividing the trip up into accelerating, constant and deccelerating parts. My sketch would look kind of like a number line, and I'd write in what was given and what I could find out about each part.
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